1. Field of the Invention
The present invention relates to an elongated filter system, the elongated filter system having an elongated alignment means associated therewith, filter element assemblies for the elongated filter system, wherein the filter element assemblies are constructed solely of combustible materials thus allowing the filter element assemblies to be completely incinerable. One of the filter element assemblies is constructed without a center supporting tube and another of the filter element assemblies is constructed utilizing a center supporting tube, end pieces and filter element all constructed solely of combustible material.
2. Description of the Related Art
In industrial or automotive filtering applications, the material which is to be filtered often contains contaminants which must be removed and disposed of as hazardous waste. One of the acceptable ways of disposing of many types of hazardous waste is incineration performed by a licensed hazardous waste disposal facility.
One problem which previous filter systems present is that the filter element onto which the contaminates adhere has generally contained a metal or other rigid, non-combustible center support member. Therefore, it is known to manufacture a filter element having a rigid center support tube. For instance, see U.S. Pat. No. 3,786,926 issued on Jan. 22, 1974 to John R. Wilhelm, or U.S. Pat. No. 2,843,269 issued on May 16, 1955 to Emery Dudinec. In order to incinerate these filter elements, the support member must either be manually removed from the filter element prior to the incineration and then separately disposed of as hazardous waste or, alternately, the entire filter element must be shredded prior to incineration.
It is also known to make a pleated paper filter element having the ends thereof captured in a thermoplastic material, such material being commonly known as "Plastisol". For instance, see U.S. Pat. No. 2,732,031 issued on Jan. 24, 1956 to Milton Rabbitt and Carl Binder; U.S. Pat. No. 2,771,156 issued on Nov. 20, 1956 to Walter Kasten and Abbott Rohn; and U.S. Pat. No. 3,106,528 issued on Oct. 8, 1963 to Roland Burks.
Removal of the center support member prior to incineration presents safety problems to the workers performing the removal, adds to the cost of disposal, and increases the risk of liability to the company generating the waste. This increase in risk of liability is due to the fact that the removed support members are considered hazardous waste which must be disposed of in a licensed hazardous waste landfill. As a contributor to a hazardous waste landfill which may sometime be declared a Superfund site, the generating company, the disposal company and any transporting company which was employed to deliver the support members to the landfill, may all face future liability for the disposal. Thus, both the generating company and the disposal company would prefer to avoid this option since under current hazardous disposable waste laws, they remain liable for their hazardous waste from `cradle-to-grave`.
On the other hand, in order for the entire filter element to be incinerated, a disposal facility must first be located which has the capacity of shredding materials prior to incineration. Second, since the non-combustible elements of the filter element will pass through the hazardous waste incinerator and will exit as solid waste which is normally disposed of as hazardous waste in a hazardous waste landfill, the generating company retains the potential Superfund liability with this option also. This is true, despite the fact that the material is not hazardous waste, since all contributors to a landfill which later becomes a Superfund site are liable for ensuing cleanup costs regardless of the types of materials they contributed. For these reasons, shredding and incinerating the entire filter elements is also an unattractive option.
The only other viable option available for disposal of most filter elements is to bury the entire filter element in a hazardous waste landfill. This option is costly and increases the risk of Superfund liability since the containers in which the filter elements are sealed for burial will eventually be breached by the soil's natural chemical processes, thus, releasing the contaminants into the soil and, as described above, the contributor is still liable for cleanup costs. Under Title D of the Federal Code of Regulations, this liability extends to thirty years after the disposal site is closed. Thus, to avoid potential liability, it is desirable to have completely incinerable filters.
In the making of elongated filtering systems, such as used in the filtering of aviation fuels, the disposal problem becomes particularly acute because of the extended length of the filtering elements. An equally difficult problem with elongated filtering elements arises in the installation and removal of the elements from the filtering chamber. Due to the extended length, alignment of the filter elements with the outlet port proceeds slowly sometimes requiring rigorous and/or sophisticated means of assuring alignment.
Therefore, it is known to make a filter device having a filter element carried by an inner housing in axial alignment with a rod axially aligned with a chamber of the filter device. For instance, see U.S. Pat. No. 3,239,062 issued on Mar. 8, 1966 to Nils Rosaen.
It is also known to provide an elongated, one-piece center tube assembly having expanded end portions with fine screen means disposed around an intermediate portion wherein the center tube assembly supports a soft filter cartridge comprised of a fabric bag filled with pulverulent filter medium. For instance, see U.S. Pat. No. 2,846,074 issued on Aug. 5, 1958 to Alan Brundage.
Finally, it is known to provide an elongated, removable tubular filter liner which is disposed longitudinally in the interior of an elongated filter element comprising a tubular wall wherein the tubular wall further has a guide means for urging the annular end portions of the liner into embracing relationship with the interior surface of the wall. For instance, see U.S. Pat. No. 2,891,673 issued on Jun. 23, 1959 to James Zievers.
The present invention addresses this problem by providing a filter system having a permanent center tube assembly onto which fully incinerable filter elements may be replaceably attached or by providing a filter having a center tube support, end caps and filter element all of which are capable of being reduced significantly in volume by crushing and are fully incinerable.